Kurume azaleas

Undulating rugs of colour from above - our layers of limbed up kurumes from below

Undulating rugs of colour from above - our layers of limbed up kurumes from below

The Kurume azaleas are in flower. Their small flowers are so massed that they make undulating rugs of colour in the garden with no foliage visible at all. These are evergreen azaleas and they hail from Kurume on the southern isle of Kyushu in Japan. Apparently, these are hybrids of two different Japanese species (obtusum and kiusianum) but for local gardeners, their significance is related more to the fact that they are hardier than the southern Indian evergreen azaleas and they are compact growers. Not that ours are compact and they impressed a visitor from Kyushu a couple of years ago. He spoke no English and we speak no Japanese but he managed to convey the message to us that these specimens were of astounding grandeur and they deserved more tender loving care than we were giving them. We felt suitably chastised. We limb up these azaleas to expose their wonderful trunks highlighted in white by lichens, creating another layer in the garden.

Azaleas are members of the rhododendron family but they are considerably easier to strike from cutting. Kurumes have tiny leaves to match their little flowers and can be a viable alternative for buxus hedging as they take clipping and will sprout from bare wood, although they are never as dense as buxus. They are also prized subjects for bonsai. The flowers come in shades of pink, red, white and mauve.

September 25, 2009 In the Garden

  • It is an early spring this year and as yet the season is showing no sign that it will slow down and average out. For gardeners this means heeding the warnings. Summer may arrive correspondingly early. Don’t delay on getting woody trees and shrubs planted. Get mulches onto garden beds to protect against drying out. Get any lifting and dividing of clumping plants done as soon as you can. Plant hedges without delay so the plants can settle in and get some fresh roots out before summer. Get fruit trees planted.
  • If you use hormone sprays (Tordon Gold for lawns is a common one, as is Grazon in the farming sector) put them away for the next month. Plants coming into growth are vulnerable to hormone sprays, particularly magnolias, grapes and kiwifruit. It is bad enough to affect your own plants but when your spray drift invisibly and imperceptibly descends upon your neighbours, most will be too polite to tell you what they think of you, but it won’t be good.
  • If you are growing strawberries, pinch off the first white flowers of the season which may be appearing. You want the plant to put its energy into growing larger and getting stronger before it exhausts itself setting fruit for you to eat.
  • Kumaras are one vegetable which needs maximum growing time to get a good crop. It is too early to put them in the ground yet, but you can be laying out the tubers in a warm, dark place to encourage them to start sprouting.
  • Yams can also be prepared now for planting soon. You can usually get away with using tubers from the fruit and veg section of the supermarket but sprout them first. What we grow as a yam in this country is a member of the dreaded oxalis family but they are not too keen on dry, sandy soil which heats up and burns the fleshy stems. Plant yams where they have some space to clump and spread a little and do not expect to confine them to tidy rows and get a good harvest.
  • We have been gently harvesting sapotes (the near tropical fruit from Central America with soft white flesh resembling warm icecream) and bamboo shoots. The latter we assume to be phyllostachys edulis and once they have been blanched in boiling salted water, they are pretty much identical to the ones you buy tinned. We are still eating our Hass avocados, as we have been since January. Unlike the hard avocado fruit you currently see in the supermarket where the coppery sheen tells you it has been picked too early and it will never ripen properly, ours are still from last season and taste just as they should. If you like avos, you live in a coastal area and are warm enough, this is a tree that will pay for itself as soon as it starts cropping. Just buy a grafted, named variety and don’t waste your time with a seedling.

Plants to impress in English early summer gardens.

It does appear to us at this stage as if the seasons are early this year. Mind you, winter struck early and with a vengeance so it is only fair that spring should similarly make an early appearance. With that comes a sense of panic. Should Rhododendron Rubicon be flowering in mid September and will we have any rhodos left to flower during Festival? We have enough experience to know that these things tend to even out over time and if the flowering remains early, at least our nuttalliis and maddeniis will see us through. But it has had our thoughts turning to the plants that really impressed us in an early English summer. We may need to draw on these for future festivals.

Frilly large and pink - we can't grow herbaceous peonies here
Frilly large and pink – we can’t grow herbaceous peonies here

Herbaceous peonies (or paeonia). Big frilly, fluffy, pink herbaceous peonies. They look fantastic, they need staking to stop them falling over and they don’t grow in Taranaki. Apparently they do extremely well in Central Otago and they are happy in a continental climate (dry, cold winters and hot, dry summers – rather the antithesis of here). We just have to admire them when we travel. And they are another short term wonder where they look just fantastic but then have a rather long time “passing over” as we say.

Philadelphus, aka mock orange blossom. These we can and do grow though we don’t feature them as much as we saw in England. There are a wider range on the market there, including larger flowered forms and double forms. Facetiously, I would add they probably have forms with variegated leaves too. The Brits do love their variegated foliage and their yellow foliage. These affectations add colour and texture in their climate with its diffuse light whereas we shun them here where our unfiltered sunlight burns them. The philadelphus is known as the mock orange blossom, I assume, because of its wonderful fragrance. It makes a large deciduous shrub – most forms get to 3 metres if you don’t trim them.

Cornus kousa was great all round the country. It is the dogwood from China and Japan – a small tree with flat flowers favouring pink but can also come in shades of white, cream and green tinged. We have a nice pink flowered one in our garden though it is a little poorly these days. There were a whole range of different selections in the UK, including some very large flowered ones and some top pink forms. We need to have a closer look at kousa. The American dogwood species don’t do as well for us here (they get decimated by the puriri moth) but kousa is a different story.

In the perennials, the stand out plants were alliums, verbascums, astilbes and eryngiums. Alliums are onions, though ornamental onions in this case. Some forms put up wonderfully decorative large spheres of purple and I wanted them instantly. Alas these archetypical inclusions of the English summer border are not really any easier there than here and the bulbs are often bought in annually. What a wonderful feature plant they are, though. The famous Beth Chatto Gardens list no fewer than 21 different ornamental alliums in their 2009 mailorder list.

Tulbaghia are onion relatives. English gardeners love to amass what are called National Collections of each and every plant genus, often in private gardens. We visited one garden which proudly proclaimed itself as the holder of a number of national collections, including tulbaghia. Hah, declared Mark, commenting that he thought there were only a very few different tulbaghia species. He was right. They are a small plant family, modest in number and modest in appearance. And indeed the National Collection of tulbaghia was considerably more impressive on paper than in reality. But it did give Mark a new claim to add to his repertoire. He has since been heard to proclaim: “Ah. But I have seen the national tulbaghia collection.” We do grow tulbahia violacea here but truly it looks a little chive-like.

Verbascums put up tall spires of flowers, typically yellow or white, with a rosette of leaves at the base. Great Dixter used self seeded verbascum spires as a repeated flower motif throughout the garden so we felt we were in good company as we too have a large flowered yellow form which is a biennial through our rockery. But we only have two forms and there are more than that which we will be tracking down for summer displays. We have tried and lost the most impressive verbascum, a splendid grey felted rosette with an impressive flower spire. Time to try it again.

Miss Willmott achieves immortality - eryngium giganteum
Miss Willmott achieves immortality – eryngium giganteum

Eryngiums are sometimes called sea holly and are mostly somewhat prickly. We have a lovely blue form in our rockery and it was because one was planted too close to the pathway that I discovered they have phenomenally deep and sturdy taproots. It makes them difficult to move. Eryngiums were used widely in English gardens, being tolerant of dry. There is a large form of the plant, eryngium giganteum, now called Miss Willmott’s Ghost. Said Miss W was a fine gardener but possibly a cantankerous old biddy who was a law unto herself. Allegedly, she made a practice of secretly scattering seed of eryngium giganteum in gardens that she visited so that the large, silvery plants would rise, ghost-like, long after her visit. Apparently eryngiums will seed down and many are biennial so only last two years. All I can say is the one I have in our rockery is a deciduous perennial and it has never yet self seeded, though I would be pleased if it did.

Astilbes. I fell in love with astilbes and the national collection of these at Marwood Hill in Devon was worth looking at. Big fluffy plumes in shades of white, cream, pink and rusty reds, all happy in damp areas but also preferring some shade with our harsh sun here. We visited Hollards Garden in South Taranaki last weekend and noticed their dell held the promise of a good display of astilbes later in the season. We can grow them here in the north, but they just don’t like being built up in nursery conditions (weevils seem to sniff the pots out from afar and move in) so we need to be more organised and build them up in the garden, not the nursery.

We were greatly taken with aruncus as soon as we saw it. Aruncus is a rather like a giant creamy astilbe on Eastern European steroids, ideal for wild or natural gardens. It needs space, at least a metre and a half across. We fell out of love with it equally quickly when we realised it had a short season and its beautiful creamy plumes of flowers turned brown and hung on, so it just looked burned. We noticed Persicaria polymorpha filled the same niche and a skilled gardener confirmed that this plant passed over more gracefully.

The stand out beautiful garden plant was a grass at Beth Chattos. I have now lost the piece of paper where I wrote its name down but I am sure it was a stipa. It is rather academic anyway because if there is one plant group that we will never be allowed to import new family members into this country, it will be ornamental grasses. Oh, and the ornamental thistles which looked great. The most truly awful plant we saw was widely grown, though goodness knows why. It was a thoroughly nasty spirea. Clumping yellow leaves (may even have had some sort of variegation to make it worse) contrasting with a yukky mauve pink flower. It was a good argument for glyphosate.

Rhododendron Floral Sun

Floral Sun - frilly, scented and yellow in the nuttallii range

Floral Sun - frilly, scented and yellow in the nuttallii range

Spring continues apace and as camellias and magnolias wane, it is rhododendron time starting. Floral Sun has opened her first flowers. I say her, because being frilly, scented and soft coloured, this plant looks more Venusian than Martian. It is one of ours. When Mark came home and commented that he had crossed sino nuttallii (which has big white scented trumpets) with R. W. Rye (small yellow flowers) in an attempt to get colour into the nuttalliis, I predicted he would end up with a whole lot of plants with very small white flowers and no scent. I was wrong. He ended up with a run of plants with the lovely heavy textured leaves and peeling bark of sino nutt, with frillier trumpets and yellow. Soft yellow tones, not the harder acid yellow of R. W. Rye but Floral Sun also has the more compact habit of her father Rye which is an added advantage. We are still pretty pleased with this rhododendron even if the flowering will be over long before visitors arrive for Rhododendron Festival.

September 18, 2009 In the Garden

  • We were shocked by the infestation of onion weed on the local Lepperton roadsides, spread we suspect by road works. Onion weed is a thug and not easy to get rid of. Any small bulblets that you leave will respond with renewed vigour and the most common weedkiller spray, glyphosate, doesn’t touch it in our experience. If it is a small patch in your garden, you can dig it (and then let it heat and rot in a black plastic rubbish bag left in the sun). If you are not averse to using sprays or if you have a massive swathe, try treating it like wandering jew – which usually means spraying with Amitrol. Add a surfactant to encourage it to stick to the shiny leaves.
  • With asparagus season starting, if you covet your own patch remember that asparagus is a permanent crop and grows from underground crowns which are best left undisturbed. To establish a few plants, dig the area really well, then dig it a second time and dig deeper than usual and add plenty of compost and humus. Do not harvest anything for the first couple of years because you want the crown to build up strength and size. Asparagus is a long term commitment. While bare root divisions were sold earlier in winter, what is available now will be more expensive potted crowns. You may well have more success with buying potted crowns than smaller bare root divisions.
  • Strawberries are still available and these are a cheap and cheerful crop to try with children. Planted right now, they will crop later in early summer so it is a quick turn around. If you have ever been to a PYO place, you will know that they want full sun, well tilled soil and if you plant them on a little mound, it improves the drainage and heats up faster for early growth. However it isn’t necessary to mound and it does increase drying out later. Laying some straw beneath the plants later will help keep the fruit clean and reduce disease caused by splashing. Pine needles work equally well as a mulch.
  • If you go to the garden centre and get tempted to buy little pots of tomatoes, peppers, pumpkins, courgettes, cucumbers or similar, don’t be too fast to plant them out in the open. You won’t gain anything and you are more likely to lose them when we get a cold, wet spell (which we will – it is still only early spring). Labour Weekend is the traditional time for getting these crops into the ground. Experienced gardeners may put them in earlier but usually only under a cloche (plastic or glass covers). If you have already planted them, you can salvage the situation by cutting the bottom off a 2 litre plastic bottle for an individual cloche (clear plastic or opaque will work). If you are looking at the little pots still waiting to be planted, pot them on instead to larger sized pots and keep them in a sheltered, warm spot on your verandah for a few more weeks.
  • If you feel they need it, the usual time to feed bulbs is immediately after flowering. However, many bulbs come from poor, impoverished natural environments so to be honest, we don’t feed them here as a matter of course. If you have bulbs which failed to flower this year, it may be that they are badly overcrowded and need thinning, or that their position has become too shaded.
  • Resist the temptation to tie bulb foliage into tidy knots after flowering. Nothing shouts out your ignorance more. Tying them in knots greatly reduces the bulb’s ability to store away energy through its foliage to keep its strength up, forcing it into early dormancy. If you are trying to tidy up and the foliage looks untidy, make a mini fence out of twigs or short pieces of bamboo.